const mysql = require("mysql");

var con = mysql.createConnection({
    host:'192.168.168.144',
    port:'3306',
    user:'root',
    password:'ddd',
    database:'mydatabase'
})

var userName=process.argv[2];
var selectSql = "select userName,age from users where userName=?";

con.query(selectSql,[userName],(err,result)=>{
    if(err){
        console.log(err);
    }
    else{
        var userList = result;
        for(var i=0;i<userList.length;i++){
            console.log(userList[i]['age']);
        }
    }
})